Steering wheel drive for vehicles



Aug. 22, 1944. B. w. KEESE STEERING WHEEL DRIVE FOR VEHICLES Filed Aug. 3, 1940 3 Sheets-Sheet 1 BeI/eH I/ W [feese Aug. 22, 1944.

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B. w. KEESE 2,356,164

STEERING WHEEL DRIVE FOR VEHICLES Filed Aug. 3, 1940 3 Sheets-Sheet 2 M 23 m C) 7 22 I E I I 7- Aug. 22, 1944. B. w. KEESE ,STEERING WHEEL DRIVE FOR VEHICLES Filed Aug. 3, 1940 3 Sheets-Sheet 3 Patented Aug. 22, 1944 UNITED STATES PATENT OFFICE Claims.

This invention relates to driven steering axles and methods of assembly and more particularly to driven steering axles of the full floating type and methods of assembly therefor. Various types of full floating steer drive axles are well known. Such prior axles have, however, required the use of special wheel and brake mountings with structures and bearing mountings that are comparatively difficult to adjust, and steer, and which are comparatively expensive to manufacture.

A primary object of the present invention is therefore to provide improved full floating steer drive axles which may be readily assembled, disassembled and adjusted, in novel manner.

Another object of my invention is to provide steer drive axles utilizing standard quantity production pleasure car and truck wheel and brake assemblies, yet having wheel bearings of ample capacity to withstand the stresses of steer drive operation.

A further object of the invention is to provide a novel two part sleeve and wheel supporting bearing assembly in a steering drive axle of the full floating type wherein the bearing assembly is located and adjusted prior to mounting the wheel hub.

.A further object of the invention is to provide in a steering drive axle a novel differential bowl section and spring pad construction permitting a maximum offset of the differential bowl, and providing a maximum engine pan clearance.

A still further object of the invention is to provide a novel internal pressure relief outlet for axles which prevents entry of dirt and water to the gearing when the pressure within the housing is below a predetermined level.

A still further object of the invention is to provide in a steer drive axle, a novel readily and accurately machinable swivelled housing mounted on inclined trunnions in a manner to provide effective wheel camber, and a self steering tendency.

Further objects of the invention will appear as the description proceeds in connection with the appended claims and the annexed drawings in which:

Figure 1 is a front elevation partly in section of the long side of a steering drive axle of the invention illustrating structural detalis of the wheel mounting and axle housing.

Figure 2 is a plan view of the differential bowl of the axle of Figure 1 illustrating the spring seat on the bowl cover and a check valve for ventin: the bowl.

Figure 2 illustrating the spring pad construction.

Figure 4 is a diagrammatic view illustratin my spring pressed sealing ring assembly,

Figure 5 is a top plan view of the steering arm and knuckle arrangements of the axle of Figure 1.

Figure 6 is a fragmentary view illustrating the universal connection of the steering knuckle to the tie rod.

Figure 7 is an enlarged section illustrating the split tapered bushing surrounding the bolts securing the steering arm to the steering knuckle housing.

Figure 8 is a plan view of the split bushing of Figure "I.

Figure 9 is an end view of the removable hub illustrating the wheel pulling shoulder.

Figure 10 is an end view of the nut and snap ring assembly on the threaded end of the stub shaft.

Figure 11 is a front elevation of the long side of an axle comprising a further embodiment of the invention adaptable for single or dual wheels.

Referring to Figures 1 and 2, the steer drive axle of the invention comprises a non-rotatable hollow tubular axle housing. It through which extends a driven axle shaft I2. The inner end of housing It is tightly fitted within a tubular collar II integral with differential bowl [4. As illustrated in Figure 2, housing It and collar ii are preferably rigidly attached as by rivets I5 although any suitable alternative fastening operation can be employed.

Diflerential bowl assembly The inner end of shaft I2 is provided, beyond its splined portion carrying gear It, with a button ll of reduced cross section having a convex end face it. Button ll may be made integral with shaft II, but preferably it comprises the head of a cap screw threaded into a tapped axial hole It at the end of shaft l2.

At the short side of the axle, a short axle shaft 2| carrying at its inner splined end a gear 22 extends through a tubular collar 23 integral with bowl It and carries at its inner end a button 24 similar in shape to button ll. Button 24 is provided with a shank 25 pressed within an axial bore 26 at the inner end of shaft 2|.

Button 24 is spaced from the end face of shaft 2| by a plurality of shims 21 and, when the axle shafts are correctly positioned as illustrated in Figure 1, convex face 28 of button 24 Figure 3 is a section taken along line 3-3 of is in contact with face I. of button ll.

My novel method of assembling the axle to obtain proper positioning of shafts I2 and 2| will be later described.

Gears l6 and 22 mesh with a differential gear 29 and are driven by a shaft 3| which is connected to the usual propeller shaft. Except for buttons i1 and 24 and the mechanism mounting them, all the shafts, gearing and other details within bowl I4 are conventional and do not comprise part of the invention, and in the preferred embodiment herein illustrated I employ a differential gearing assembly of the type employed in the well known Ford one-ton truck rear axle illustrated in United States Patent 1,946,051 to Herbert W. Alden.

In steering drive front axles it is desirable that the differential bowl be located as far laterally offset from the vehicle longitudinal center line as possible to avoid interference with the engine crankcase and to provide a vehicle front end of minimum height. In prior constructions the presence of spring pads on the axle housing between the differential bowl and adjacent wheel at the short side of the axle appreciably limited this oifset. I have increased the available offset for this purpose by casting the right front spring pad 32 integral with the cover section 33 of bowl l4. Pad 32 is provided with tapped holes 33 for reception of the usual spring studs.

With the vehicle operating at high speeds and under other high temperature conditions, gases are evolved within the differential bowl which tend to build up pressures within the bowl and should be vented to prevent injury to the oil seals such as seal 34. Devices for venting the bowl now employed usually comprise apertures drilled in the bowl walls and these apertures are provided with fittings providing open but tortuous passages to the atmosphere. These permanently open passages permit entry of considerable dirt and water to the interior of the bowl especially where sub-atmospheric pressures are developed within the bowl as during cooling. To prevent this entry of water and dirt I provide a check valve assembly 35 for the differential bowl, as illustrated in Figure 2.

Check valve 35 comprises a short tube 36 threadedly secured within an aperture 31 leading to the interior of bowl l4. Tube 36 has a central bore 38 terminating in a valve seat 39 closed by a ball 4|. A suitable apertured sheet metal cap 42 is fixed upon the outer end of tube 36, and a spring 43 reacting between cap 42 and ball 4| retains the ball normally on seat 39 to keep bore 38 closed.

Spring 43 is of such design that it will permit pressure within bowl H to unseat ball 4| when a predetermined pressure has been attained. This predetermined pressure is well below the limit which seal 34 and the other shaft seals are capable of withstanding without injury.

Valve 35 is hereby normally closed against entry of dirt and water and is open only under conditions during which fluid flow outwardly of the bowl only is possible. I have found that a spring pressure of about 12 to 16 ounces on bail 4| gives excellent results in service.

Wheel mounting At the long side of the axle, axle housing II is secured to a hollow tube 46 which is enlarged at its outer end to provide a cup-shaped spherical surfaced socket member 41. Tube 46 and socket 41 thereby comprise integral parts of the axle housing when assembled and are therefore non-rotatable.

Collar 46 is formed with an inclined shoulder 44 and an extension 46' of reduced external diameter beyond the shoulder. Housing II is telescoped over extension 46' until its inclined end face approaches shoulder. to provide a V- shaped notch.

A series of apertures 45 are drilled through housing II and into extension 46 to provide a series of pockets 45 in extension 46'. Housing II and extension 46' are then permanently secured together by welding in the notch between shoulder 44 and the housing end face and by rivet welding at 46 wherein the welded material bridges each aperture 45 and its associated pocket.

Alternatively housing II and collar 46 may be butt welded as disclosed in Alden Patent No. 2,075,563.

Spherical socket member 41 is provided with diametrically opposite apertures in which are press fitted cylindrical trunnions 49. A housing 49, consisting of mated upper and lower portions 5| and 52 secured as by bolts 53, has spherical surfaces fitting about socket'41.

Each housing portion is formed with an integral hollow projection 54 having cylindrical internal walls 55 accessible for machining through an aperture 56 at the end of projection 54. Trunnions 48 fit within projections 54 and are surrounded by a sleeve of elongated roller bearings 51, preferably of the needle type, arranged on walls 55.

Trunnions 48 are hardened ground steel and to prevent undue wear on projection 54, which is usually a relatively soft forging, I provide a hardened steel crowned washer 59 of larger diameter than aperture 56 seated on the annular machined surface 55' at the bottom of each projection 54 and bearing on the end face of each trunnion. The crown of washer 56 is adjacent the trunnion end face and is sufiiciently large to prevent undue friction with the trunnion end faces, but it is also designed to provide sufficient area of contact between the washers and trunnion end faces to carry the thrust load exerted by the trunnions as housing 49 rocks thereabout.

The parts are designed with a total clearance of .005 inch between top washer 56 and the end face of its associated trunnion. This enables an oil film to be maintained between the upper trunnion and washer assembly.

The weight of joint 11 and the accurate seating of washer 59 on lower surface 66' closes aperture 56 against entry of dirt and water and prevents leakage of oil from the housing. Housing portions 5| and 52 are formed with mating grooves 59 carrying an annular ring 6| of sealing felt or like material engaging the spherical surface of socket 41. To insure a tight seal at this point I provide a substantially circular band 62 of fiat crimped spring metal extending along the bottoms of grooves 59 (Figure 4). Spring 62 maintains sealing felt 6| tightly against socket 41 at all times during rocking of housing 49.

Rocking of housing 49 about trunnion 49 is effected by a steering arm 63 formed at its free end with a ball 64 for universal connection to the usual steering gear assembly of the vehicle. Arm 63 is formed with a flat flanged end 66 apertured at 66 to receive a plurality of studs 61 extending therethrough into threaded apertures 68 in housing portion 5|. Apertures is are tapered and of appreciably larger diameter than studs 81.

Each stud 81 is surrounded by a split tapered bushing 88 located mainly in tapered aperture 88 but spaced above housing portion as illustrated in Figure 5. Beyond bushing 88, each stud 81 is provided with a split lock washer 1| and a nut 12.

As each nut 12 is tightened, bushing 88 is forced downwardly along stud 81 and is securely wedged between the stud and aperture 88. The bushing is circumferentially contracted during this operation and stud 81 is placed under shear stresses as the bushing travels down inclined aperture 88. This assembly is quick and easy, and centers and binds studs 81. against accidental rotation.

Lower housing portion 52 is formed with an integral arm 13 which carries a downwardly extending ball headed stud 14 (Figure 6) fitting within a cooperating socket 15 at the end of a tie rod 18. The other end of tie rod 18 is similarly universally connected to an arm similar to arm 13 and extending from a housing identical with housing 48 at the short side of the axle.

Within socket 41, shaft I2 is connected by a constant velocity universal joint 11 to a stub shaft 18 which extends through the wheel. Joint 11 may be of any suitable constant velocity type, but as shown is of the so-called Bendix-Weiss type in which the ball and slot connection between the parts is such as to permit substantial axial separation of the shaft sections. The inward movements of shafts l2 and 2| are, however, limited by buttons l1 and 24.

The center of joint 11, as illustrated in Figure 1, lies in the line joining the axes of trunnions 48. This line is inclined at an axis of about 9 /2 degrees to the vertical to provide the necessary castef for steering purposes.

The axis of shaft 18 is inclined at about 2 degrees to the axis of shaft [2 to provide desired camber. In order to properly locate shaft 1.8 in this relation to shaft I2, I machine the abutting faces 18 and 8| of housing portions 5| and 52 so that when housing 48 is assembled by tightening bolts 53, faces 18, 8| lie in a transverse plane containing the axis of shaft 18. The angle of camber is indicated at A in Figure 1.

I Housing 48 has its outer face 82 machined to lie in a plane disposed at 90 to faces 18 and 8|. A hollow spindle 83 surrounding shaft 18 has its inner face 84 machined to flt flush with face 82 and is secured rigidly to housing 48 as by bolts 85. In this manner the inclination of housing face 82 alone determines the angle of camber of the stub shaft. "Spindle face 84 is normal to the spindle axis and therefore I am enabled to machine the spindle and assemble the bearing and hubstructures thereon without forming specially inclined faces on the spindle or hub, thereby providing for maximum ease and accuracy of machining of these parts, and hence maximum accuracy of bearing alignment and mounting. Any small inaccuracy in the angle of face 82 results only in a slight change in camber angle, which is not serious.

Provision of camber as above described brings the point at which the center of the tire periphery contacts the ground close to the trunnion axis. This results in easy steering.

Furthermore steering movement of the spindle 83, due to the inclined trunnion axis, tends to raise the axle. The load on the axle resists raising of the axle and results in a tendency of the 15 wheels to return to straight ahead position. This self steering tendencyis also an aid to easy steering.

The lower races of a pair of spaced tapered wheel supporting roller bearing assemblies 88 and 81 are press fitted on spindle 88. A collar 88 spaces the bearing assemblies being disposed between the outer races. The outer end or spindle 88 is externally threaded and provided with a suitable lock nut arrangement 88 for locating and adjusting the bearings on the spindle. Bearing 81 is larger than outer bearing 88. The purpose of this arrangement is to provide sumcient bearing capacity to enable the use of standard pleasure car wheels and brakes upon the axle of the invention. Such pleasure car wheels are relatively low in cost and of sumcient strength for steer drive of axles of lower capacities. For example, Chevrolet wheels and brakes are suitable for ton capacity axles of this ty The use of such wheels and brakes therefore contributes to economy in manufacture and production emciency.

Wheel hub 8| is non-rotatably mounted on the tapered splined section 82 of shaft 18. The inner race of bearing 81 abuts against a shoulder 88 on spindle 83. The outer race of bearing 81 is fitted into a recessed shoulder 84 cut in a substantially annular collar 85 surrounding the spindle inwardly of bearing 81. In assembling the bearing before adjustment, collar 85 is slid over spindle 83 and then bearing 81 is advanced against shoulder 83.

The upper race of bearing 81 and an oil seal 86 between collar 85 and spindle 83 temporarily support collar 85 at this stage. Then spacer 88 and bearing 88 are mounted on the sleeve and lock nut assembly 88 is manipulated in the usual manner to obtain and set proper adjustment for the bearings.

Wheel hub 8|, which is formed with an internally splined collar 88 fitting with tapered spline shaft section 82, is then forced on shaft 18. Spaced bolts 81 are employed to secure the irmer hub flange 88 to collar 85. As bolts 81 are drawn tight, the outer races of bearings 88 and 81 are drawn tight against an internal shoulder 88 in hub 8|, spacer 88 and shoulder 84. Collar 85 thereby effectively becomes an integral part of the hub.

A suitable grease cup IN is provided on hub 8|. Oil seal 88 prevents escape of grease from the bearing chamber to the brake or other wheel mechanism. A soft oil-tight gasket I88 is employed between hub flange 88 and collar 85.

As illustrated in Figure 1, a pneumatic tired ground engaging wheel N2 is mounted on hub 8|. Hub flange 88 is provided with a plurality of non-rotatable bolts I83 extending through aligned apertures in the wheel and suitable nuts |88a are employed to secure the hub flange and wheel together. Brake drum |83b is also secured to hub flange 88 by tightening nuts |83a on bolts I83. A suitable hydraulic brake operating cylinder |83c on the stationary brake mechanism support 83d actuates the usual pivoted brake shoes |83e into contact with the inner braking surface of drum l83b. Support |83d is secured to spindle 83 by bolts 85 which secure the spindle to housing 48. While any suitable wheel and brake assembly may be employed at I82 and |83a| 83c, I have illustrated standard Chevrolet pleasure car wheels and hydraulic brake assembly which are available in quantity production.

Bolts 85 also clamp upon the brake support I02d a dirt seal element I03! which is formed with an inclined portion I039 extending to sealwith opposed fiat peripheral surfaces I04 and opposed radially projecting integral formations I05 providing wheel puller shoulders for use in removing hub 9I when desired. Wheel-puller prongs may be inserted over surfaces I04 and then rotated in back of projections I05 for the purpose of pulling hub 9| ofi tapered splines 92.

Figures 1 and 10 illustrate a novel nut locking device. The end of shaft 18 is threaded at I08 to receive a nut I01 having a plurality of radial bores I00 connected by a circumferential groove I09. Shaft section I 06 is formed with an axial keyway III. A snap ring of relatively heavy spring wire is formed with an arcuate portion II2 terminating at one end in an inward radial spur II9. Spur H9 is of such length that when nut I01 is turned to place a bore I08 in alignment with keyway III, spur II 3 is thrust into the aligned bore until its end is disposed in the keyway as shown in Figure 10, and then arcuate ring portion H2 is snapped into groove I09.

This snap ring locks nut I01 against rotation as effectively as a cotter key and is more reliable than a cotter key in that its inherent resiliency keeps it snugly on the nut. Further my snap ring has none of the objectionable sharp projecting edges of the usual cotter key and is safer to handle.

Assembly method In assembling the axle, because of the structure of the constant velocity joint illustrated, care must be taken that shafts I2 and 2I have proper axial spacing. Accordingly, I first assemble the long side of the axle into the position illustrated in Figures 1 and 2 wherein fixed button I1 is seated at the inner end of shaft I2 and its surface I8 lies adjacent the center line of pinion 29 and the universal joint center lies in the trunnion axis. During assembly of the long side of the axle, I adjust bearing assemblies 86 and 81 prior to mounting hub 9| as above explained.

This setting of the long side of the axle is not disturbed during the remainder of the assembly. The reason for selecting long shaft I2 for carrying the fixed button I1 is solely that shaft I2 offers slightly more difliculty in handling than shorter shaft 2I in the manipulations to be herein described. It is therefore within the scope of the invention to provide the fixed button on either shaft I2 or 2I and manipulate the other in the manner to be described.

The universal joint and sleeve and hub arrangements at the short side of the axle are identical with those disclosed in Figure 1 and are therefore not illustrated or described to avoid needless repetition. The tubular axle housing at the short side of the axle corresponding to housing II is secured to bowl collar 23 by the riveting operation employed at the long side of the axle. Reference to corresponding numerals will be employed in the following assembly description for the short side of the axle.

With long shaft I2 in position. the first step Is to select a button 24 with a shank having a light tap fit in hole 26. I tap this button toward the planar end face 20 of the short shaft 2| until the planar under side 24 of button 24 is spaced about one-half inch from face 29. This distance may of course vary with the type of button or the size of the differential assembly. Shims 21, Illustrated in Figure 2, are not yet provided so that button 24 can be displaced further toward face 20 upon application of suitable axial pressure.

I then insert shaft 2I, with universal joint 11 and stub shaft 18 attached, into the short side of axle housing and differential bowl I4 until the button end faces II and 20 are in light contact. This can be determined by a slight axial pressure insufi'lcient to displace button 24.

I then assemble housing 40 on socket member 41 and secure spindle 02 to the housing by tightening at least two bolts 85. In this operation. care is taken not to push snort shai't 2I inwardly further than required by assembly of housing 49. Any necessary inward displacement of shaft 2I during this operation, however, shifts button 24 toward face 20.

I then assemble collar 95. bearing assemblies 90, 81, spacer and hub member M on spindle 93 in the manner above described. Only one nut of assembly 09 is employed to hold the bearings in position, reserving final adjustment to a later step. Especial care must be taken, while fitting hub collar upon splined shaft section 92, not to push shaft 2I inwardly. To this end I first draw up nut I01 tightly to insure location of hub member 9| in its correct axial position relative to shaft 10, and then tighten bolts 91.

Gasket I00 is omitted during this opergtion and at least two bolts 91 are tightened to draw the hub members and bearing assembly tight. This operation results in a further slight inward displacement of shaft 2I with consequent shifting of button 24 toward face 20 unless, of course. the shaft is already properly located.

I then dismantle the above temporary assembly by removing bolts 91 and 95 and dismounting housing 49, care being taken not to push shaft 2| further inwardly. Shaft 2I is then pulled out and the axial distance between faces 24' and 29 measured accurately.

Tap fit button 24 is removed from the end of shaft 2I. A shim pack 21 of a thickness equal to this measured distance is made up and placed on a button 24 identical with the removed tap fit button but having a press fit shank 20 within hole 26. Preferably shim tolerances are +0 and --s; inches. Button 24 is pressed tightly inwardly until shim pack 21 is solid and this is the final position of button 24 on shaft 2I.

Housing 49 is then remounted on socket member 41 and spindle 83 secured thereto. All bolts 85 are tightened in this operation which is a final assembly step. Then collar 95, bearing assemblies 06, 81 and spacer 08 are remounted on spindle 83. Both lock nuts 09 are employed in this operation during which bearings 06 and 41 are adjusted to final position.

Hub member 9| is then attached to the shaft and collar 95. During this operation, gasket III is placed between the hub and collar, and in addition I place a shim of selected thickness between the hub and collar coextensive with gasket III. In the illustrated assembly, good results are obtained by employing a shim in inches thick.

Such a shim effectively increases the length of the hub axially of the axle so that, when the hub is tightened to flnal position by drawing up on all bolts 81, the inner face 28 of button 24 is spaced from face I8 of button H a distance equal to the combined shim and gasket thickness at I88 as a minimum, or a distance equal to the above minimum plus 9; inch as a maximum.

In any event, the spacing between shafts I2 and 2| within the differential bowl can be selected within in inch limits by suitable combined shim and gasket thicknesses at I88.

The above-described method of assembly is simple and speedy and can be accomplished by any ordinary mechanic following given directions.

Further embodiment Figure 11 illustrates an embodiment of the invention wherein the hub construction is designed to utilize wheels and brakes that match with standard dual type rear truck wheels on a steerdrive axle.

This axle is mainly of the same construction as Figure 1, corresponding parts being indicated by the same numerals, and differs therefrom substantially only by the hub and bearing arrangements hereinafter described.

Hollow spindle 83 is secured to housing 49 by bolts 85 which also secure the brake supporting flange 88 to the 'housing. 'Inner large bearing assembly 81 is mounted on spindle 83 with its lower race seated against shoulder 93 as in Figure 1. Spaced outer bearing assembly 88 is also mounted on sleeve 83, but instead of the spacer collar 88 of Figure l, the adjacent ends of the outer races of bearings 86 and 81 are seated against shoulders I3I and I32, respectively, formed in hub member I33.

Pressed into a bore in the inner end of hub I33 is a flanged sheet metal seal receiving sleeve I34 which receives lubricant seal 98. A grease cup I38 of suitable design is provided on hub member I 33.

The outer end of hub I33 is formed with a plurality of tapped holes I38 in which are threaded studs I31. A hub cap I38, having a central portion internally splined to interflt with tapered splined shaft section 92, has a radial flange I39 apertured to fit over studs I31. Suitable nut and lock washer assemblies I are employed on studs I31 to draw hub cap I38 tightly against inner hub member I34. A suitable grease tight gasket I42 is clamped between hub cap I38 against hub member I34.

Inner hub member I33 is formed with a wide integral radial flange I43 in which is non-rotatably seated a circumferential row of bolts I44 adapted to project through suitable apertures in la! vgheel I45. Nuts I48 secure a wheel I45 to the The single wheel I45 as illustrated matches 'with a standard type of rear dual truck wheel.

If desired, however, for heavier dut axles, dual wheels may be used since flange I43 is of such The bolt and snap ring assembly I01 above described is used to lock the hub against outward axial movement on shaft I8.

Assembly of this embodiment of the invention is substantially the same as in that of Figures 1 and 2. The combined shim and gasket thickness at I42 determines the axial spacing of the long and short axle shafts.

The invention may be embodied in other speciflc forms without departing from the spirit or essential characteristics thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

What is claimed and desired to be secured by United States Letters Patent is:

1. In a steer drive axle; an axle housing having an enlarged socket member at its end; an axle shaft in said housing; axially aligned trunnions on said socket member; a split housing comprising upper and lower housing portions secured about said socket member rockable upon said trunnions, said housing portions having abutting faces lying in a common substantially transverse plane inclined at a small angle to the axis of said axle shaft and having aligned end faces normal to said plane; a hollow spindle having said housing end faces so that the spindle axisis inclined at said angle to said axle shaft axis; a stub shaft projecting axially through said spindle; and a universal joint connecting said shafts at said socket member.

2. In a steer drive axle, a rockable hollow spindle, a rotatable stub shaft extending through said spindle, spaced bearing assemblies on said spindle, means on said spindle for adjusting said bearing assemblies, a hub collar disposed axially inwardly of the inner bearing assembly, an outer hub member non-rotatably secured eupon said stub shaft and rotatably carried by said bearing assemblies and means rigidly securing said hub member to said collar.

3. In a steer drive axle, a swiveled hollow spindle, a rotatable stub shaft extending through said spindle, a splined section on said shaft beyond said spindle, axially spaced bearings supported on said spindle, with the innermost hearing being of larger capacity than the outermost bearing, an inner hub member disposed inwardly of the innermost bearing, an outer hub member secured upon said splined shaft section and rotatably carried by said bearings, and means securing said hub members together.

4. In a steer drive axle, an axle housing having an enlarged end socket; axially aligned upper and lower trunnions on said socket; a steering knuckle housing on said socket member rockable about said trunnions; integral cup-shaped top and bottom projections on said steering knuckle housing surrounding said trunnions, the bottom projection having an apertured end wall of a diameter smaller than the cup; cylindrical roller sleeves between the inner walls of said projections and said trunnions, and upper and lower hardened thrust bearing members between the ends of said trunnions and closing said cupshaped projections, the bottom member seating against the bottom of said bottom cup-shaped projection adjacent the apertured wall thereof lower trunnion. I

6. In a steer drive axle assembly, a rockably mounted hollow spindle which is non-rotatable about its longitudinal axis, a rotatable stub shaft extending through said spindle, said shaft terminating in a splined section and a threaded section in order, an elongated open-ended hub member surrounding and substantially coextensive longitudinally with said spindle and widely axially spaced bearings'between said hub member and spindle, a substantially radial flange on said hub member and means on said flange for attachment of a vehicle wheel, an internally splined hub cap mounted on the splined section of said shaft and having a radial flange rigidly secured to said hub member, a fastening element on the threaded section of said shaft for retaining said hub cap on said splined section of the shaft, and a grease seal between the inner end of said hub member and said spindle.

7. In a full floating steer drive axle assembly, a non-rotatable axle housing having a rotatable axle shaft therein; a hollow wheel-supported spindle swingably mounted on trunnions on said axle housing; a stub shaft extending through said spindle and a constant velocity universal joint connecting said stub shaft to said axle shaft, said shaft terminating exteriorly of said spindle in a tapered splined section and a threaded section in order; an internally tapered splined cap member mounted on the splined section of said shaft and having a radial flange; a wheel hub surrounding said spindle and journalled on widely axially spaced bearings between said hub and said spindle; means for rigidly securing said hub to the flange of said cap member; and means secured to the threaded portion of said stub shaft for restraining said cap and hub against axial displacement.

8. In a full floating steer drive axle assembly, a stationary housing having opposed trunnions;

anaxleshaftinsaidstaticnaryhousing; shallow spindle mounted for steering movement on said tnmnions2apairof comparativelywidelyspaced anti-friction bearmgs mounted on said spindle: ahub memberhavingasleoveportionsubstmtially co-extensive with said bearings and supported thereon for accurate rotation about the axis of said spindle; a stub shaft extending through said spindle in spaced relationship to the walls thereof; means mmmting said stub shaft for accurate rotation about the axis of said spindle, including a connection carried by said hub having internally splined surfaces tightly fltting tapered splines on the outer end of said stub shaft; means for maintaining said splined connection in assembled relationship: and a constant velocity universal joint connecting said stub shaft to said axle shaft and having an axis of oscillation substantially aligning with the axis of said trunnions, said splined connection affording the sole support for said stub shaft and the outer end of said axle shaft, whereby said stub shaft may flex radially in response to minor misalignment of said universal joint with said trunnion axis.

9. In a steer drive axle, a rockable hollow spindle; a rotatable stub shaft extending through said spindle; spaced inboard and outboard bearings on said spindle, each comprising inner and outer races and interposed rolling elements: a hub collar disposed axially inwardly of the inboard bearing and having a shoulder engaging the inner face of the outer race thereof; an outer hub member non-rotatably secured to said stub shaft and rotatably carried by said bearing assemblies and having a shoulder abutting the outer face of the outer race of said inboard bearing; and means rigidly securing said hub member to said collar and clamping the outer race of said inboard bearing between their respective shoulders.

10. The steer drive axle defined in claim 9, together with a sleeve-like spacer member disposed inside said hub member and abutting the neighboring faces of the outer races of said bearings.

BEVERLY W. KEESE. 

